Bernard mcgilvray



(No Model.) I B. MoGILVRAY.

WRENCH.

No. 481,506. Patented Aug. 23, 1892.

lllll wm Y 77 W UNITED STATES PATENT OFFICE.

BERNARD MCGILVRAY, OF WASHINGTON, DISTRICT OF COLUMBIA, ASSIGNOR OFONE-HALF TO FREDERIO W. RITTER, J R., OF SAME PLACE.

WRENCH.

SPECIFICATION forming part of Letters Patent No. 481,506, dated August23, 1892.

Application filed May 10, 1892. Serial No. 432,496. (No model.)

To all whom it may concern.-

Be it known that I, BERNARD MCGILVRAY, a citizen of the United States,residing at Washington city, in the District of Columbia, have inventedcertain new and useful Improvements in Wrenches; and I hereby declarethe following to be a full, clear, and exact description of the same,reference being had to the accompanying drawings, in which- Figure l isa perspective view of a wrench embodying my invention adjusted for useas an ordinary monkey-wrench. Fig. 2 is a perspective view, partlybroken away, of the same wrench adjusted as a pipe-wrench; and Fig. 3 isa detached View of the interposed loose gripper-jaw.

Like symbols refer to like parts Wherever they occur.

The object of my invention is to produce a strong and efficientconvertible wrench which, while being substantially the wellknown andfavorite monkey-wrench of universal use, can at will be changed into anefficient pipe-wrench.

To this end the main feature of my invention, broadly stated, embracesthe combination, with the usual heads of the monkeywrench havingparallel jaws, one of which shall have a serrated face, of an interposedloose or sliding gripper plate or jaw having its faces parallel, one ofits faces serrated to coact with theserrated face of the wrenchaw.

There are other minor features of invention, all as will hereinaftermore fully appear.

I will now proceed to describe rnyinvention more fully, so that othersskilled in the art to which it appertains may apply the same.

In the drawings, 1 indicates the usual fixed or hammer head of amonkey-wrench, and 2 the movable head, said heads forming parallel jaws,one of which is serrated, as at a, or provided with an equivalentgripping-face.

3 is the shank on which the movable head 2 slides, 4: the set or powerscrew, and 5 the milled wheel by which the screw 4: is operated.

In order to increase the power which may be applied to screw 4 when thedevices are used as a pipe-wrench, the milled wheel 5 is provided with aseries of holes 6 for the insertion of a nail or equivalent lever.

7 indicates a loose gripper-jaw, having one of its faces serrated, as atb, to coact with the serrated face of the wrench-head, and saidserrations are preferably counterparts of those on the head, so thatwhen the loose plate or gripper-jaw is in the position indicated in Fig.l the loose gripper-jaw or plate 7 is supported against twistingstrains. This loose jaw or plate 7 is slotted, as at 8, for the passageof the shank 3, and if the preferred arrangement of serration abovespecified is employed it will also serve to prevent undue strain on theslotted or Weakest portion of said movable plate or gripper-jaw.

When deemed desirable, spring-piece 9, having teeth 10 10, may besecured to or formed on the loose gripper-jaw 7, and in the heads 1 and2 indentations 11 11 may be formed as a means for temporarily securingthe loose gripper-jaw 7 in either of the positions shown in Figs. 1 and2; but for ordinary work no such spring-catch will be required.

Having thus described my invention, What I claim, and desire to secureby Letters Patent, is

1. The combination, with a monkey-wrench having parallel jaws, one ofwhich is plain and the other serrated, of an interposed movablegripper-plate having parallel faces, one of which is plain and the otherserrated, to correspond and coact with the respective plain and serratedfaces of the parallel jaws of the monkey-wrench, substantially as andfor the purposes specified.

. 2. The combination, with a monkey-wrench having parallel jaws, one ofwhich is plain and the other serrated, said jaws provided with lateralindentations, of a movable gripper-plate having parallel faces, one ofwhich is plain and the other serrated, to coact with the correspondingjaws of the monkeywrench, and a spring-plate secured to the movablegripper-plate and adapted to engage the indentations in the jaws of saidmonkeywrench,substantially as and for the purposes specified.

In testimony whereof I affix my signature, in presence of two witnesses,this 10th day of May, 1892.

BERNARD MOGILVRAY.

Witnesses:

F. R. CORNWALL, PERCY B. HILLS.

